Interface‐Engineered PVDF / BaTiO ₃ Composite Nanofibers With Amino‐Terminated Liquid Butadiene Rubber for Flexible Piezoelectric Energy Harvesting

Self‐powered flexible piezoelectric devices based on polyvinylidene fluoride (PVDF) face a critical trade‐off between piezoelectric output and mechanical flexibility. In this study, an amine‐terminated liquid butadiene rubber (ATPB) toughened PVDF/BaTiO 3 (BTO) flexible nanofiber membrane is fabricated via electrospinning to achieve an optimized balance between piezoelectric output and mechanical durability. The ATPB coating serves as a low‐modulus elastomeric interphase on BTO nanoparticles, mitigating the modulus mismatch and suppressing interfacial stress concentration while maintaining high ductility, with elongation at break exceeding 33%. Through the combined effects of chemical hydrogen bonding from ATPB and heterogeneous nucleation of BTO, the relative content of polar β‐phase reaches 62.4% (Lambert–Beer law) and 60.1% (multi‐peak intensity ratio method), with a β‐phase absolute crystallinity of 33.38%. The assembled piezoelectric nanogenerator (PENG) produces a stable open‐circuit voltage of 10–15 V, representing an approximately 2–3 fold enhancement over pure PVDF devices. The short‐circuit current reaches 7 μA, with a peak power density of ~4 μW cm −2 , and the device retains ~92.3% output after 5000 cycles. This research provides an effective strategy for developing flexible PVDF‐based materials for energy harvesting and wearable sensors.